This PCB takes a 7-bit binary input
ABCDEFG and decodes the binary into two BCD characters (tens place and ones place).
A is the MSB and
G is the LSB of the binary input.
This PCB uses a custom-programmed ROM (27C256 OTP) to generate 8-bits of BCD for each binary number. Two 7447 chips are used to decode each segment on a two-digit common-anode display (MAN6410), one for each digit (tens/ones).
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